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Gross return to corn acres through cattle feeding as influenced by choice of harvest endpoint
Forty-nine Charolais x Red Angus steers (initial average BW = 526 kg) were fed individually in a Calan-Broadbent feeding system to evaluate performance and interactions resulting from performance and crop yield when corn is harvested as either silage (SIL), earlage (EAR), high-moisture corn (HMC), or corn (DRC). Steers were randomly allocated to 1 of 4 dietary treatments where SIL, EAR, HMC, or DRC constituted 75% of diet DM. Remaining of SIL, EAR, HMC and DRC diet contained 11% haylage (0% for SIL), 10% modified wet corn distillers grains (MDGS), 4% liquid supplement with Rumensin (SUPP) and 11% DRC (SIL). Gross return (gross $/hd) was determined as dollars remaining after subtracting non-corn crop expenses (cattle purchase, veterinary medicine, yardage, bedding and other feed ingredient) from gross cattle sale. Worth of each corn crop endpoint was determined from corn grain worth ($/25.4 kg) and its relationship to corn grain content in SIL, EAR, HMC crops This value was compared to SIL, EAR, HMC worth determined by ANOVA (gross $/hd divided by 1,000 kg) . Worth of each corn crop endpoint was also determined by dividing gross return (gross $/hd) by acres used to raise crop. The former method is used to determine corn crop endpoint worth for a feeder that purchases crops (owns no land) and the latter is used to determine corn crop endpoint worth for a feeder who owns corn land. Cattle fed HMC had the lowest (P ≤ 0.05) DMI. Cattle fed DRC gained at faster (P < 0.05) ADG than cattle fed the other corn crops. Cattle fed HMC had greater ADG (P < 0.05) than those fed SIL or EAR. No difference between cattle fed DRC or HMC was observed for G:F, but feeding either led to greater (P < 0.05) feed conversion than SIL or EAR. Final BW and HCW were greatest for DRC (P < 0.05), intermediate (P < 0.05) for HMC and lowest (P < 0.05) for EAR and SIL. There was a tendency (P = 0.08) for treatment effect on fat thickness wherein cattle fed DRC or HMC tended to have greater fat thickness than those fed SIL. No treatment differences were found for REA or marbling. Worth (gross $return/1,000 kg) of SIL, EAR or HMC was greater than that of DRC. Harvesting corn as either SIL, EAR, HMC or DRC had no impact (P > 0.05) on crop worth (gross $ return/acre).
Keywords:
feedlot performance, corn, crops